rust-changelog: introducing ChangelogEntry, a unique handle to access all data
Everything should be explained in changeset descriptions.
Further notes:
- there are no consumers of
data_for_revin the entire Mercurial code base - backwards compatibility is maintained.
- my current experimental RHGitaly implementation uses the new
ChangelogEntryand passes all tests against this topic (gitaly-comparisonis the job for functional tests)